Polyester resins are widely used in reinforced plastics, paints, films, and resins for molding, and also used as fabric materials to produce clothing due to characteristics of superior heat resistance, mechanical strength and elastic strength.
Recently, use of polyester resins in the fields of interior building materials or molded sign panels is increasing because of the characteristic physical properties. However, polyester resins have lower heat resistance than other polymer materials, for example, acrylic materials or polycarbonate materials, and thus there is a problem that polyester resins are not suitable for exterior building materials under severe change of seasonal temperature.
Meanwhile, polycarbonate resins are used in a variety of fields of building materials and housings for electronic products, packaging materials, cases, boxes, and interior/exterior building materials due to excellent properties of impact resistance or heat resistance. Demands for such polycarbonate resins are increasing owing to excellent mechanical property, but there are problems that discoloration or cracking of polycarbonate products may occur by frequently used cleaners, cosmetics for women, or hand sanitizers for infants, or deterioration of polycarbonate products may occur by various household chemicals.
There have been many attempts to solve the problems of the polyester resins or polycarbonate resins, and studies on blending of the polyester resins with the polycarbonate resins have been conducted.
Further, a technique of improving impact resistance and heat resistance by blending an acrylonitrile-butadiene-styrene-based graft copolymer (ABS) with a polycarbonate resin has been developed, but there is a limitation in that the product is not an environmentally friendly biomass product. Meanwhile, since the polyester resin and the polycarbonate resin are different from each other in terms of melting point and molecular structure, it is difficult to improve heat resistance only by simple blending thereof. Further, many methods have been used in order to improve chemical resistance while maintaining mechanical property of polycarbonate, in particular, heat resistance, but there were problems that the improvement of chemical resistance is not enough to be practically applied to industries, and appearance of a resin product is deteriorated. Furthermore, a method of further blending with one or more materials has been attempted in order to improve heat resistance and chemical resistance at the same time, but it was difficult to obtain satisfactory chemical resistance.
Meanwhile, an engineering plastic, of which use is rapidly growing, is ABS (acrylonitrile-butadiene-styrene) or PC/ABS (polycarbonate/ABS). By applying excellent heat resistance, impact resistance, and self-extinguishing property of PC and processability and economic advantages of ABS, PC/ABS has been developed. In terms of chemical resistance, however, PC/ABS is susceptible to most chemicals, such as aromatic hydrocarbons, acetone, and alcohols. When PC/ABS is directly exposed to these chemicals for a long period of time, its discoloration, swelling, and cracking occur to deteriorate the value of the product. Therefore, many studies have been conducted to prepare a resin composition having superior chemical resistance to the conventional heat resistant ABS or PC/ABS. For example, it was reported that polyolefin-based resins having excellent chemical resistance are mixed and used in order to improve chemical resistance of ABS. However, there are problems that a block copolymer must be used as a compatibilizer in order to improve compatibility of incompatible materials, and phase separation occurs when practically applied, leading to a rapid reduction in mechanical properties.